This invention relates to position determination systems. Specifically, the present invention relates to an apparatus and a method for updating data.
Satellite positioning system (SATPOS) devices that determine position using the satellites of the US Global Positioning System (GPS) are commonly used for navigation of vessels, vehicles, airplanes, and other conveyances. SATPOS devices are also used for surveying, construction site planning and management, mining, oil and gas exploration and development, etc. Also, handheld SATPOS devices are used for personal navigation, data collection, data maintenance, etc.
SATPOS devices are quite effective for indicating the position of the SATPOS device. Position is typically indicated using either an alphanumeric indication of position or by displaying a map that indicates position. Alphanumeric indications of position typically include coordinates such as, for example, Latitude and Longitude, World Geodetic Survey (WGS) Coordinates, etc.
Map displays typically indicate position by an icon or other indicator visible on a map. One such map display, typically referred to as a moving map display, displays the position of the SATPOS in the center of the displayed map. Such map displays typically are oriented such that the top of the SATPOS device""s display indicates North (either magnetic North or true North). That is, irrespective of the direction in which the SATPOS device is actually oriented, North is shown at the top of the display. For users that intuitively know which direction is North, such maps are adequate for locating features displayed on the map. However, for users that do not know where North is, or when visibility is obscured such that the user cannot determine where North is, such maps are inadequate for guiding the user to a destination or to a feature displayed on the map.
For many commercial applications of SATPOS systems, such as construction site planning and management, surveying, navigation, etc., it is essential that an operator be able to locate features displayed on the map. Such users typically operate a separate device for indicating direction such as a conventional magnetic compass.
Some SATPOS devices indicate the direction of movement of the SATPOS device, typically referred to as xe2x80x9cheading.xe2x80x9d Typically, heading is determined by analysis of determined position in relation to prior determinations of position as the SATPOS moves. Typically, SATPOS devices that indicate heading use a map display oriented such that the top of the SATPOS unit (e.g., the top of the unit""s display) corresponds to North (either magnetic North or true North).
Some prior art SATPOS devices orient the displayed map such that the top of the SATPOS unit (e.g., the top of the unit""s display) corresponds to the direction of movement calculated by the SATPOS device. This gives a good approximation of the user""s heading as long as the user continues to move and as long as the SATPOS unit is oriented in the direction of movement, allowing a user to easily determine the location of features visible on the display. However, when the SATPOS device stops moving, determination of heading can no longer be made. Some SATPOS systems maintain the previous heading for orienting the moving map display for a given time interval. Other prior art SATPOS systems default to positioning North at the top of the map. This can be quite confusing to the user.
Recently, digital compasses have been developed that can indicate direction. However, digital compasses must be calibrated to properly align the digital compass prior to use. Also, each time that magnetic environment around the compass changes, the digital compass must be recalibrated. Digital compasses are typically calibrated by moving the digital compass in a full horizontal arc. The calibration process takes time and is prone to operator error. Also, calibration error can occur as a result local magnetic anomalies.
Some applications such as Graphical Information System (GIS) applications, data maintenance applications, etc. require updates to a remote database. In addition, the user needs to be able to determine the location of nearby features for updating information relating to the feature. Some prior art SATPOS devices used in GIS and data maintenance applications store mapping data for an entire geographic region in the memory of the SATPOS device. However, the storage of such large amounts of mapping data on each SATPOS device requires each SATPOS device to have extensive memory storage, adding to the cost of the SATPOS device.
What is needed is a method and apparatus for providing an accurate indication of heading to a user of a SATPOS device. Also, a method and apparatus is needed that meets the above needs and that accurately indicates direction when the SATPOS is not moving. Also, a method and apparatus is needed that can communicate with remote sites and that is easy to use. Moreover, a method and apparatus is needed that allows for updating data in a remote database and allows for easily determining of the location of features located near the SATPOS. The present invention meets the above needs.
The present invention provides an integrated position and direction system that that accurately indicates direction and heading. The integrated position and direction system includes a digital compass for indicating direction when the integrated position and direction system is not moving. In addition, the integrated position and direction system of the present invention includes a communication module for communicating with remote sites. Moreover, the method and apparatus of the present invention allows for updating data in a remote database. Furthermore, the location of nearby features are easily determined.
An integrated position and direction system is disclosed that includes a SATPOS having a receiver adapted to receive satellite position determining signals. The integrated position and direction system of the present invention also includes a digital compass that is adapted to determine direction. In one embodiment, a controller is used to control the operations of the integrated position and direction system.
In one embodiment of the present invention, when the SATPOS is moving, the direction of movement or xe2x80x9cheadingxe2x80x9d determined by the SATPOS is indicated on the display. When the SATPOS is not moving, the direction given by the digital compass is indicated on the display. Therefore, while the SATPOS is moving, the heading is indicated, and when the SATPOS is not moving, direction is indicated using the digital compass. Thus, the present invention provides a method and apparatus for providing an accurate indication of both heading and direction to a user of a SATPOS device.
In one embodiment of the present invention, the integrated position and direction system includes a radio communication module. The radio communication module allows for communication with remote devices and remote sites using wireless communication methods. In the present embodiment, the radio communication module communicates through radio transmissions with a cellular communication system.
Methods for updating data are disclosed in which the integrated position and direction system communicates with a remote site for both uploading and downloading data. Data is downloaded to the integrated position and direction system and is updated such that only data relating to features located near the current position of the position and direction system is downloaded. The received data is then used to generate a display that indicates features located near the integrated position and direction system. The display indicates the orientation and position of the features relative to the integrated position and direction system.
Data in a remote database is updated with user input that is received at the integrated position and direction system. The user input and a determination of position (that represents the position at which the user input was received) are sent to a remote computing device. The user input and the determined position are then used to update the remote database.
Because the display indicates the correct orientation of features, the features are easy to find. Also because the integrated position and direction system of the present invention only downloads data that relates to features located near the current position of the integrated position and direction system, there is no need to store extensive amounts of data on the integrated position and direction system. Thereby, significant cost savings are realized
The methods and apparatus of the present invention provide for easily updating data (both data stored on the integrated position and direction system and data stored in a remote database) using a radio communication module that communicates with a remote computing device. The apparatus and methods of the present invention allow for easily updating data in a remote database and allow for easily determining the location of features.
These and other objects and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments that are illustrated in the various drawing figures.